There are a wide variety of units, known to those skilled in art, for metering fluids in amounts needed to meet the operational requirements of the equipment to which the fluids are delivered. Currently, the regulators of liquid petroleum gas fueled vehicles typically include an integral vaporizer to generate saturated vapor that is burned as fuel in the engine of the vehicle. Other regulators, differently arranged, are used in vapor fed systems in conjunction with a discrete vaporizer to provide the liquid petroleum gas to the regulator and, in turn, to the engine to burn as fuel. These regulators have a fixed output pressure.
Many of the liquid petroleum gas regulators known to those skilled in the art fall short of operating with the desired efficiency. This is so because the regulators function without control of the changing operational requirements of the engine to which the liquid petroleum gas vapor is supplied.
In contrast, U.S. Pat. No. 3,741,240 to Berriman is an example of a fluid regulator that operates in response to the operational demands of remote fluid utilization equipment. The range of control of the regulator disclosed in this patent, however, is somewhat limited by the use of a thin metal flexible diaphragm that responds to pressures changes in the output fluid flow and the level of the vacuum from the manifold to regulate the output pressure.